For this project, all you have to do is glue the four tiles together to form a box. Use painter's tape to hold the tiles in place until the adhesive dries completely. It's a good idea to let the planter cure for around a week or follow the manufacturer's recommended curing time before filling the planter. Fill the box with good quality potting mix, and select some pretty plants to grow in it. You could even use five tiles so that these planters actually have a base, or, if you're using small tiles, cut down a soda bottle to squeeze inside the cube.